SAN FRANCISCO, CA - JANUARY 22: Vials of the Fluvirin influenza vaccine are displayed at a Walgreens phramacy on January 22, 2018 in San Francisco, California. A strong strain of H3N2 influenza has claimed the lives of 74 Californians under the age of 65 since the flu season began in October of last year. People are being encouraged to get flu shots even through the vaccine has been only 30% effective in combating the influenza. (Photo by Justin Sullivan/Getty Images)

SAN FRANCISCO, CA - JANUARY 22: A sign advertising flu shots is displayed at a Walgreens phramacy on January 22, 2018 in San Francisco, California. A strong strain of H3N2 influenza has claimed the lives of 74 Californians under the age of 65 since the flu season began in October of last year. People are being encouraged to get flu shots even through the vaccine has been only 30% effective in combating the influenza. (Photo by Justin Sullivan/Getty Images)